The present disclosure relates to a compressed natural gas fueling station.
Conventional compressed natural gas (CNG) fueling stations for CNG vehicles and tanks require separate on-site installation and custom, underground wiring to operate. Compressor, truss lighting, heaters and other devices and systems for CNG fueling stations require additional amperage to power the devices. This requires bespoke in-ground electric wiring to separate, on-site power sources to run the higher voltage devices.
In conventional compressor systems for CNG stations, I/O compressor boards are mounted on the back of a controller, which is housed in a separate location from the compressors. Accordingly, signal wiring and electronic wiring for each compressor are run to the I/O compressor boards mounted on the back of the controller. Thus, in a conventional compressor installation, this can require up to 7-8 electrical conduits per compressor, and 20 or more electrical conduits total, distributed throughout the installation to the controller—over a mile of wiring.
In short, conventional CNG fueling stations are built as permanent installations at sites. Structures, systems and electronics are custom built and installed as a permanent station. There has been no conception of a portable, all-in-one “plug-and-play” CNG fueling station.
Disclosed are embodiments of systems and methods for a portable, modular CNG fueling station. In an embodiment, the modular compressed natural gas (CNG) fueling station comprises a compressor module configured to house a CNG compressor unit for the CNG fueling station. The compressor module comprises a compressor module connection interface component. The CNG fueling station also comprises a control module comprising a control module connection interface component. The CNG fueling station also comprises an interface module that comprises electrical conduits connecting the compressor module connection interface component to the control module connection interface component to operatively connect the compressor module to the control module. The CNG fueling station also includes a fueling station module comprising a utility gas inlet operatively connected to the compressor module. The CNG fueling station also comprises a priority panel configured to control compressed natural gas flow for the fueling station module. The CNG fueling station module includes fueling inlets and outlets that can be connected on either side of the CNG station. The modular CNG fueling station is configured with preinstalled electrical conduits and valving.
The connection interface of the control module, the interface module, and the connection interface of the compressor module are configured to be installed and connected above-ground on a site. The interface module includes an electrically insulated casing enclosing the electrical conduits connecting the compressor module connection interface component to the control module connection interface. The casing is adapted and safety rated to allow the electrical conduits to operate above-ground. When the control module is connected to a power source and the fueling station module is connected to a CNG fueling source, the station is fully operational.
The CNG station includes housing having an open floor plan with electrical conduits in a sub-floor. The housing of the compressor module is configured to improve cooling, heating and prevent water intrusion. The CNG station also includes modular, removable compressor units. Each compressor and its electrical and plumbing components are configured to be installed and removed as a single module, and each compressor can run independently of the others. This allows for easy installation and deinstallation of the compressors as well as easy service.
Remote I/O, transducers and digital outs to relays are controlled by “smart block” I/O compressor boards. The compressor boards are mounted on the compressor panel in the compressor module. Accordingly, only a single control signal line needs to be run from a controller in the control module to the compressor boards.
The control station module is configured with a transformer configured to provide a plurality of different voltages from a power source to differently powered devices of the modular CNG fueling station.
In an embodiment, the fueling station module is configured to provide defueling of CNG vehicles. The compressor module can include a defuel priority panel that is configured to defuel a CNG vehicle. The defuel and priority panel is also configured to store defueled gas in defuel storage tanks, which can then be used to later fuel or refuel CNG vehicles and CNG vessels. In an embodiment, the defuel priority panel can direct the defueled gas to fuel other CNG vehicles at the panel fueling and defueling site. Storage tanks can be provided directly on the compressor module at the fueling station module.
Embodiments are illustrated in the figures of the accompanying drawings, which are meant to be exemplary and not limiting, and in which like references are intended to refer to like or corresponding things.
Various embodiments now will be described more fully hereinafter with reference to the accompanying drawings, which form a part hereof, and which show, by way of illustration, specific embodiments by which the innovations described herein can be practiced. The embodiments can, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the embodiments to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense.
Throughout the specification and claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise. The term “herein” refers to the specification, claims, and drawings associated with the current application. The phrase “in an embodiment” as used herein does not necessarily refer to the same embodiment, though it can. Furthermore, the phrase “in another embodiment” as used herein does not necessarily refer to a different embodiment, although it can. Thus, as described below, various embodiments can be readily combined, without departing from the scope or spirit of the disclosure.
In addition, as used herein, the term “or” is an inclusive “or” operator and is equivalent to the term “and/or” unless the context clearly dictates otherwise. The term “based on” is not exclusive and allows for being based on additional factors not described, unless the context clearly dictates otherwise. In addition, throughout the specification, the meaning of “a”, “an”, and “the” include plural references.
Embodiments disclosed herein provide a system, devices, and methods for a modular CNG fueling station.
The CNG station 100 is configured to have a length, height and weight to allow it to be easily moved and transported on a standard semi-tractor-trailer truck or transport truck without the need for special permitting. For example, in the embodiment, the CNG station has a weight of about 43,000 pounds, with the compressor module 120 weighing about 33,000 pounds and the control station module 101 weighing about 10,000 pounds. The CNG station 100 is also outfitted with components for easy lifting and placement, such as a 10 foot spreader bar and lifting lugs 111.
In an embodiment, the modular CNG station 100 can also run from a generator. The exterior of the control room 109 comprises external connectors 144 to connect to external devices. The external connectors 144 includes sockets 102 for conduits to site heaters, for example truss block heaters, and sockets 103 for lighting, for example truss lighting. The control room's 109 external connectors 144 also includes sockets 105 for DCI communication connections and sockets 106 for ESD circuits. The control station module 101 is thereby provided with external connectors 144 for powering external devices for the CNG station 100 environment, such as lighting and heating. The control station module 101 also includes an antenna 112 for wireless communication with the compressor module 120.
In an embodiment, as shown in
The control station module 101 is configured to operate the compressor and fueling functions. As shown in
As shown in
The interface module 124 encases connecting cables that are pre-wired to connect to the connection interface 140 of the control station module 101 and a connection interface 155 of the compressor module 120. The interface module 124 comprises a plurality of flexible cables housed in the interface module 124 enclosure. For example, in an embodiment, the interface module 124 can have 10 flexible Meltric connectors (not shown), which can be connected to the external connections of the control station module's connection interface 140 and the external connections of the connection interface 155 of the compressor module 120 in as little as 30 minutes. As explained herein, the interface module 124 is configured to be set on the platform 108 above-ground.
In an embodiment,
The compressor module 120 of the portable CNG station 100 includes an open floor plan with conduits in a sub-floor 130 and removable compressor units 136. As shown in
An exemplary advantage of a plurality of individually independent compressors 136 includes the ability to isolate compressor units 138, thus allowing continued operation if a compressor 136 stops operation or needs service. Accordingly, the compressor module 120 and the compressor units 138 also have a “plug and play” design that allows for easy installation and deinstallation of the compressors 136 as well as easy service.
As shown in
The CNG station 100 also includes a fueling station module 110 and a priority panel 200. A priority panel is a valving system and control configured to direct fill a vehicle or time fill multiple vehicles at the same time as well as connect a dispenser to a utility natural gas provider for public fueling of vehicles with CNG. In an embodiment, as shown in
As shown in
An I/O compressor board 150 is run to the I/O interconnect panel 185 to control each compressor 136. To reduce wiring, the I/O compressor board 150 at the compressor module 120 is connected to I/O interconnect panel 185 for communication with the control panel 180 (see
In an embodiment, the I/O interconnect panel 185 is configured to centralize sensor signals from the compressors 136, the lighting 146, the dryer 211, the priority panel 200, and the ESD switches 148. The I/O controls 185 can communicate with the control panel 180 to allow a reduction in conduit connections. As shown in
It was appreciated that in order to provide a remote CFS control panel 185 that could fuel vehicle fleets of 10-20 vehicles and upward, conventionally, fixed connections between a control module 101 and a compressor module 120 would have required up to 7-8 conduits per compressor. The I/O control panel 185 reduces over 20 conduits and wiring structures—over a mile of wiring—thus allowing for portability and simplified “plug and play” configuration for the CFS station 100 as described herein.
As shown in
If defueling capability is included, the fueling station module 110 can also include defuel storage tanks 201 for time fill, direct fill, and defueling and a buffer storage tank 261. For example, as shown in
As shown in
The system comprises a plurality of CNG storage tanks 201 in an enclosed rack. In an embodiment, the system comprises dedicated defueling storage tanks 201 for defueling and dedicated buffer storage vessels 261 for direct filling.
The Priority/Defuel panel 200 and the fueling station 110 module is configured to direct fill a vehicle, time fill multiple vehicles at the same time, and connect dispensing outlets 116,117,118 for public fueling and defueling vehicles. Priority fueling prioritizes which type of fueling needs to take place between a direct fill and a time fill for vehicle fueling. Direct fill refers to a dedicated fill where a single vehicle or fuel tanks therefor are filled at higher priority. Time fill refers to a time regulated fill where CNG is delivered to a fleet of vehicles over time (e.g. 30-40 trucks). In an embodiment, the system is configured to pull utility gas from a utility gas station via a utility gas line 215 and route the gas through a dryer 211 to an available compressor 136 on a compressed gas line 210. The compressed gas sent is then filtered by a set of final discharge filters and sent to the priority panel 200 via a compressed gas line 210. The priority panel 200 then prioritizes the CNG for the direct fill outlet 117 via a direct fill line 206 for direct filling a vehicle or for the time fill outlet 118 via the time fill line 205 for time filling multiple vehicles. As shown in
In an embodiment, the priority panel 200 can be configured to only provide direct fill and time fill, and not provide defuel capability. If defuel capability is provided, the fueling station module 110 is configured with a defuel inlet 116 to defuel a vehicle of CNG, compress the defueled CNG, and store the compressed CNG in a defuel storage tank 261. A defuel priority panel and the CNG flows are described in U.S. Provisional Patent Application No. 62/873,667 entitled Defuel Priority Panel, filed on Jul. 12, 2019, the entirety of which is incorporated by reference herein. As described therein, the priority panel 200 can be a standalone component, however the priority panel 200 can also be configured to be incorporated into the present portable CFS station 100 as described herein. A defuel priority panel 200 is configured to route defueled gas from a defueling vehicle via a defuel line 203 to a fueling direct fill vehicle or fueling time fill vehicles. When defueling gas pressure equalizes in the system, the defuel priority panel is configured to route the defueled gas to a compressor inlet 244 and the compressed gas line 210 to an available compressor 136 to compress the gas to a fueling vehicle or storage tank 201. The fueling station module 110 is also provided with a vent line 207 to vent CNG, for example if the storage tanks are full and a vehicle is still defueling, or if the CNG needs to be vented for service.
In an embodiment, a CNG vehicle can be connected to a remote mounted defuel hose (not shown) that is plumbed to the Priority/Defuel panel via a defuel inlet 116. In an embodiment, once connected, the Defuel/Priority system can be fully automated. The system is configured with a defuel line pressure transducer 321 that senses the pressure increase on the defuel line 203. That pressure increase on the defuel line 203 starts a chain of events controlled by a PLC controller 180.
First, the controller 180 activates a heat exchange system 367 configured to prevent freezing during the defuel process. In an embodiment, the heat exchange system comprises a three-stage heat and pressure regulator(s). The heat exchange system 367 comprises a glycol pump 363 and glycol heater 164. The glycol pump 363 pulls glycol from a storage tank 366, through an instant inline heater 364. This glycol is instantly heated to 180 degrees. The heated glycol is first pushed through a high-pressure heat exchanger 365. This heat exchanger 365 is configured to preheat the incoming gas entering the valve panel, which enters the system from up to 4500 psi, depending on the vehicle pressure. After the heat exchanger 365, the gas travels through a defuel valve 345 and to a manifold 368 to corresponding glycol defuel pressure regulators 328. A glycol exit of the heat exchanger 365 feeds a manifold 168 that distributes glycol to the manifold comprising defueling pressure regulators 328.
The pressure regulators 328 are preconfigured to transfer fuel at a static rate as well as to have heat applied to counteract the freezing that happens from the pressure drop. For example, the pressure reducing valves of the defuel pressure regulators 328 can depressurize fuel at 100 cubic standard feet per minute (scfm) each and are each individually heated by the glycol pump. The defuel pressure regulators 328 drop the fuel pressure from the vehicle to a set low pressure, for example from 4200 psi to 250-300 psi into a manifold, which is located inside the glycol storage tank 366. As will be appreciated, while high and low tank and defuel pressures are given with respect to exemplary CNG vehicles and vehicle tanks (e.g. 4200 psi to 250-300 psi), the defuel pressure regulators can be set to depressurize for other higher and lower pressures. After the glycol is distributed to the defuel pressure regulators 328, the glycol returns to the storage tank 366. The storage tank 366 also acts as the final heat exchanger for the defuel gas system. This is the final stage of heat exchange for the gas as it travels back out of the panel and into the utility gas compressor inlet 244 of the compressor(s) 136. Accordingly, the glycol heat exchange system 367 is a loop system, thus the glycol can always be reused, reheated and sent back through the heat exchange process. As will be appreciated, the defuel pressure regulators 328 can be set to any low pressure setting to defuel from a high pressure to a low pressure. For example, a given vehicle's tank operation can require 300 psi to operate, so the system is configured to regulate the pressure to 300 psi. In another embodiment, the system can be configured to set to 250 psi, for example, to obtain more fuel efficiency or other benefits.
As a result, the system is configured to defuel gas from a vehicle tank back into the utility compressor inlet line 244 of the compressor(s) 136 so it can be reused. A glycol suction hose 308 and pump 363 picks up cold glycol solution at a bottom of the tank and reheats it for further heat exchange during rapid depressurization. Although glycol is given as an exemplary heat exchange liquid herein, other liquids with antifreeze and heat exchange properties can be employed in the heat exchange system 367. Also, although the heat exchange system 367 is shown as a three-stage system, the heat exchange system could be configured as more or less stages, a two-stage or one stage system, for example, by removing one or both of the pre-heat exchanger 365 and the heat exchanger 366 at the storage tank. Or, another heat exchanger could be added, for example, to handle a larger depressurization differential over a short period of time.
During this time, the controller commands the compressor 136 to run. If the compressor is already running, filling time fill or direct fill, the defueled gas is directed toward the demand already in place. If there is no demand on the system, the compressor is commanded to run and the defuel vehicle gas is compressed into the onboard defuel storage tank(s) 201. The compressors will continue to run until the defuel vehicle is down to a User Set Point, for example 250 psi-300 psi. The controller 180 can be configured to automatically shut down the compressor if it is no longer otherwise needed.
In an embodiment, the Defuel/Priority panel system 200 is configured to depressurize fuel stored by the system in the defuel storage tanks 201, referred to as a storage run down. Any time there is a demand for fuel, the controller 180 can be configured to determine if there is fuel available in the defuel storage tank 201 first. As an example, if time fill is active, and the defuel storage tank 201 has fuel or is full of fuel, the system 200 can be configured to use fuel from the defuel storage tank 201 first. Thus, the system can be configured so that the storage vessels 201 are empty for the next vehicle to be defueled. To do this, each time there is demand on the system and the defuel storage tank 201 is full or has fuel, a run down valve 343 opens. This allows gas from defuel storage tank 201 to flow through the defuel regulators 328 once again. This takes the high pressure CNG from the defuel storage tanks and regulates it down to 250-300 psi to be reused into the compressor inlet 244. A defuel valve 345 is closed and the gas returns along the same path in the opposite direction on the defuel line 203 that a defueled vehicle gas takes during a defuel event to run down (i.e. defuel) the defuel storage tank(s) 201 for use by the fuel demand source.
In an embodiment, the system can be configured as an “all in one” system with on board storage or external remote mounted storage. The defuel station is configured to combat the freezing effect of defueling gas and that is used to defuel vehicle gas via a priority system to a direct flow per demand.
Accordingly, the defuel priority panel 200 can be configured to prioritize defueled gas from a vehicle or a storage tank over utility gas. This provides great advantages in both environmental safety and efficiency, as most defueled gas is not vented to the air and wasted, but is instead stored and used as fuel. Provision of a defuel priority panel 200 in a portable CNG station 100 allows the delivery and ready installation of such capability in a small, single footprint.
Note the terms “fuel”, “gas”, “natural gas” and CNG are used interchangeably herein.
In an embodiment, the system includes a control panel 180 as shown in
The following reference numbers are used on the Figures and description herein:
direct fill pressure gauge 301
time fill pressure gauge 302
defuel storage pressure gauge 303
buffer storage pressure gauge 304
truck defuel pressure gauge 305
defuel upstream pressure gauge 306
defuel manifold pressure gauge 307
control gas pressure gauge 308
direct fill purge valve 309
time fill purge valve 310
defuel storage purge valve 311
buffer storage purge valve 312
vehicle defuel purge valve 313
defuel upstream purge valve 314
defuel manifold purge valve 315
control gas purge valve 316
direct fill pressure transducer 317
time fill pressure transducer 318
defuel storage pressure transducer 319
buffer storage pressure transducer 320
defuel line pressure transducer 321
defuel upstream pressure transducer 322
defuel manifold pressure transducer 323
control gas pressure transducer 324
control gas pressure regulator #1325
control gas pressure regulator #2326
back pressure regulator 327
defueling pressure regulator (quantity of 4) 328
control gas safety relief valve 329
direct fill safety relief valve 330
time fill safety relief valve 331
defuel downstream safety relief valve 332
direct fill and buffer storage solenoid valve 333
time fill solenoid valve 334
defuel storage solenoid valve 335
run down solenoid valve 336
defuel solenoid valve 337
ESD solenoid valve 338
defuel vent solenoid valve 339
direct fill valve 340
time fill valve 341
defuel storage valve 342
run down valve 343
defuel valve 345
buffer storage valve 346
defuel vent valve 347
control gas isolation valve 348
control gas bypass valve 349
vent stack drain valve 350
buffer storage isolation valve 351
defuel storage isolation valve 352
defuel regulator isolation valve (qty of 4) 353
Gauge and valve panel 354
main inlet check valve 355
direct fill check valve 356
time fill check valve 357
buffer storage check valve 358
defuel storage check valve 359
defuel hose check valve 360
defuel manifold check valve 361
backpressure check valve 362
glycol pump 363
glycol heater 164
heat exchanger 365
storage tank and heat exchanger 366
a heat exchange system 367
manifold 368
control panel/controller 180
power panel 190
defuel storage tank 201
defuel inlet 116
defuel line 203
compressor inlet 244
time fill line 205
direct fill line 206
buffer storage line 307
glycol suction hose 308
compressor discharge inlet 309
compressed gas line 210
buffer storage tank 261
run down line 212
It will be understood that flowchart illustrations, and combinations of flowchart illustration, can be implemented by computer program instructions. These program instructions can be provided to a processor to produce a machine, such that the instructions, which execute on the processor, create means for implementing the actions specified in the flowchart block or blocks. The computer program instructions can be executed by a processor to cause a series of operational steps to be performed by the processor to produce a computer-implemented process such that the instructions, which execute on the processor to provide steps for implementing the actions specified in the flowchart block or blocks.
Accordingly, blocks of the flowchart illustration support combinations of means for performing the specified actions, combinations of steps for performing the specified actions and program instruction means for performing the specified actions. It will also be understood that each block of the flowchart illustration, and combinations of blocks in the flowchart illustration, can be implemented by special purpose hardware-based systems, which perform the specified actions or steps, or combinations of special purpose hardware and computer instructions. The foregoing example should not be construed as limiting and/or exhaustive, but rather, an illustrative use case to show an implementation of at least one of the various embodiments.